What happened
On October 25, 2019, a Piper 28-140, registration HK1598G, was conducting solo training maneuvers at the Guaymaral Aerodrome (SKGY) in Colombia. During the initial climb following takeoff from runway 11, the student pilot noticed the aircraft was unable to maintain sufficient altitude, accompanied by a slight decrease in engine RPM.
As the aircraft entered a turn during the departure, the pilot reported the situation to Air Traffic Control. While another instructor on frequency provided guidance to attempt to recover the aircraft or locate a landing site, the student pilot ultimately decided to perform an emergency landing in an unprepared field in the Torca area of Bogotá. During the maneuver, the left wing of the aircraft struck an electric pole, causing significant structural damage, including the separation of the left wingtip and deformation of the nose gear. The engine stopped abruptly upon impact. The student pilot, who was the sole occupant, evacuated the aircraft unharmed.
The investigation
The GRIAA investigation focused on the engine performance and the pilot's operational procedures. Investigators examined the aircraft's maintenance records, which showed the engine and airframe were within their service intervals. The investigation also reviewed the flight training program of the flight school (ADEVIA) and the student's recent training history, noting that the student was performing only his second solo flight.
Findings
- The primary cause of the emergency landing was an improper fuel-air mixture adjustment, which was not appropriate for the density altitude conditions of the flight. This led to irregular combustion, a loss of engine RPM, and a subsequent loss of airspeed and altitude.
- The student pilot focused on maintaining a specific airspeed of 70 knots despite the loss of altitude, which hindered effective emergency management.
- A contributing factor was identified as weaknesses in the flight school's training processes, specifically regarding the identification and management of engine performance emergencies during solo flight operations.